Final answer:
The occurrence of shortness of breath in a client after receiving ceftazidime could indicate an allergic reaction, warranting an incident report, given the known penicillin allergy.
Step-by-step explanation:
The nurse should identify reporting shortness of breath (SOB) as an indication that she should complete an incident report. Ceftazidime, a cephalosporin antibiotic, can cross-react with penicillin in individuals with penicillin allergies. As such, the client's shortness of breath could be an early sign of an allergic reaction or anaphylaxis, which is a medical emergency. This is a critical situation, especially given the client's severe allergy to penicillin, and it necessitates immediate medical attention and documentation.